How to calculate required size of VisualElement or at least text width before it is drawn?

With IMGUI, it was possible to use GUIStyle.CalcSize to calculate the required width of a label. For example:

GUI.skin.label.CalcSize(guiContent)

This made it possible to calculate the required size of a popup window before it was opened, for example. Because I knew the number of elements I wanted to draw, I could simply precalculate the size for each element and then set the window width to the minimum size.

How would I do the same with UIElement Labels or even better arbitrary VisualElements? I know there is the resolvedStyle property, but for this to work, the element need to be renderer on screen already and queried after the GeometryChanged event. This means that my EditorWindow will flicker for one frame when opening.

Other than that, there is the MeasureTextSize method, but it has the same limitation that the label must be on screen before I can measure it.

I need this to work on arbitrary labels, because I'm showing a list of GameObject names and want to calculate the widest text label. I can't hardcode the width ahead of time. Alternatively, it would equally well, if it were possible to make the EditorWindow automatically fit the size of its content, but that doesn't seem possible.

 

I also would like to know how to do this.

 

It's been a few months, still learning UI Toolkit and still trying to implement a popup window that fits the size of its content. I still can't get this to work. Does anyone know how to do this with the new system?

I have a ListView in an EditorWindow. So far, the ListView has flexGrow 1 so that it expands, but this makes the window drive the list, but I want it to be the other way around. I've tried playing with layout settings and the use the GeometryChangedEvent to see if the resolvedStyle showed any value, but it only ever repeated the window size or was zero.

So, the other approach would be to calculate the space required before opening the window, but there's no method to check how big a label will need to be to fit its text and so on. There must be some way. I believe the GraphView API grows its nodes to fit the title content, but I haven't found where exactly this happens in the source code.

 

this would be great to know

 

The function you are looking for is https://docs.unity3d.com/2021.2/Doc...e/UIElements.TextElement.MeasureTextSize.html
text size is available in LateUpdate and probably in GeometryChangedEvent as well

 

Actually just found another way to do it, would work for anything not just text. Scale the window to an unreasonable size (lets say 2000x2000) and after its contents are initialized scale it down to the largest element width (and/or height).